390506 has 4 divisors (see below), whose sum is σ = 585762. Its totient is φ = 195252.

The previous prime is 390503. The next prime is 390527. The reversal of 390506 is 605093.

390506 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 605093 = 19 ⋅31847.

It can be written as a sum of positive squares in only one way, i.e., 354025 + 36481 = 595^2 + 191^2 .

It is a zygodrome in base 4.

It is not an unprimeable number, because it can be changed into a prime (390503) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 97625 + ... + 97628.

2³⁹⁰⁵⁰⁶ is an apocalyptic number.

390506 is a deficient number, since it is larger than the sum of its proper divisors (195256).

390506 is a wasteful number, since it uses less digits than its factorization.

390506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 195255.

The product of its (nonzero) digits is 810, while the sum is 23.

The square root of 390506 is about 624.9047927485. The cubic root of 390506 is about 73.0930195950.

Adding to 390506 its reverse (605093), we get a palindrome (995599).

It can be divided in two parts, 3 and 90506, that added together give a palindrome (90509).

The spelling of 390506 in words is "three hundred ninety thousand, five hundred six".